/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package com.yunfeng.game.proxy;

import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.socks.SocksAuthResponse;
import io.netty.handler.codec.socks.SocksAuthScheme;
import io.netty.handler.codec.socks.SocksAuthStatus;
import io.netty.handler.codec.socks.SocksCmdRequest;
import io.netty.handler.codec.socks.SocksCmdRequestDecoder;
import io.netty.handler.codec.socks.SocksCmdType;
import io.netty.handler.codec.socks.SocksInitResponse;
import io.netty.handler.codec.socks.SocksRequest;
import io.netty.handler.codec.socks.SocksRequestType;

@ChannelHandler.Sharable
public final class SocksServerHandler extends
		SimpleChannelInboundHandler<SocksRequest> {

	@Override
	public void channelRead0(ChannelHandlerContext ctx,
			SocksRequest socksRequest) throws Exception {
		SocksRequestType srt = socksRequest.requestType();
		switch (srt) {
		case INIT: {
			// auth support example
			// ctx.pipeline().addFirst(new SocksAuthRequestDecoder());
			// ctx.write(new SocksInitResponse(SocksAuthScheme.AUTH_PASSWORD));
			ctx.pipeline().addFirst(new SocksCmdRequestDecoder());
			ctx.write(new SocksInitResponse(SocksAuthScheme.NO_AUTH));
			break;
		}
		case AUTH: {
			ctx.pipeline().addFirst(new SocksCmdRequestDecoder());
			ctx.write(new SocksAuthResponse(SocksAuthStatus.SUCCESS));
			break;
		}
		case CMD: {
			SocksCmdRequest req = (SocksCmdRequest) socksRequest;
			if (req.cmdType() == SocksCmdType.CONNECT) {
				ctx.pipeline().addLast(new SocksServerConnectHandler());
				ctx.pipeline().remove(this);
				ctx.fireChannelRead(socksRequest);
			} else {
				ctx.close();
			}
			break;
		}
		case UNKNOWN: {
			ctx.pipeline().addLast(new SocksServerConnectHandler());
			ctx.pipeline().remove(this);
			ctx.fireChannelRead(socksRequest);
			break;
		}
		}
	}

	@Override
	public void channelReadComplete(ChannelHandlerContext ctx) {
		ctx.flush();
	}

	@Override
	public void exceptionCaught(ChannelHandlerContext ctx, Throwable throwable) {
		throwable.printStackTrace();
		SocksServerUtils.closeOnFlush(ctx.channel());
	}
}
